TRUMPETER SWAN SURVEY of the ROCKY MOUNTAIN POPULATION, U.S. BREEDING SEGMENT FALL 2004

• Main Author: Dubovsky, James A.
• Format: Text
• Language: unknown
• Published: DigitalCommons@University of Nebraska - Lincoln 2004
• Subjects: Swan Surveys
• Online Access: https://digitalcommons.unl.edu/usfwspubs/504; https://digitalcommons.unl.edu/context/usfwspubs/article/1494/viewcontent/survey_fall2004.pdf

Observers counted 417 swans (white birds and cygnets) in the U.S. Breeding Segment of the Rocky Mountain Population of trumpeter swans during fall of 2004, a count identical to that from comparable areas last year. The numbers of white birds and cygnets in the tri-state region were essentially unchanged from respective counts in 2003. The numbers of young produced in each of the 3 states in which the Tri-state Area Flocks nest were nearly the same as those of last year. The number of white birds increased slightly in Idaho, decreased slightly in Wyoming, and was unchanged in Montana compared to counts in 2003. The number of birds in restoration flocks (Malheur and Ruby Lake National Wildlife Refuges only) also was nearly the same compared to the count from last year; the count of white birds decreased slightly, but production at Malheur improved. For the fourth consecutive year, swans at Ruby Lake produced no young. The tri-state area continues to experience severe drought conditions, with Palmer Drought Index values during early fall of 2004 among the lowest recorded since swan surveys were initiated in the 1930s.